Hello,

I've installed Exchange 2013 on Windows Server 2008 R2 where Windows Defender is now running.

Can Windows Defender interfere with Exchange services, files ?

Should I make exclusions following an article:
https://technet.microsoft.com/en-us/library/bb332342%28v=exchg.150%29.aspx  ?

While I haven't used Windows Defender in an Exchange Deployment, but I would say yes you should exclude any Exchange related files from anything that acts as an AV or anti-spyware/malware product.